What is the relationship between the human faculty for language and the many other, nonlinguistic cognitive abilities we possess? For the past decade, our research team has explored this important question by focusing on a place (quite literally) where linguistic and nonlinguistic processes seem to meet:Broca's area. Long described of as the seat of some linguistic specialization, Broca's area may have more in common with the rest of prefrontal cortex than is typically thought. Motivated by an extensive literature on the regulatory functions of prefrontal cortex, we have developed a framework for considering the role of Broca's area - a part of prefrontal cortex - in language processing. Weargue that Broca's area functions to bias competitive interactions among representations of many types (including semantic, phonological, and syntactic). As such, the relationship between Broca's area and linguistic function cannot be captured by studying a single domain (such as syntax) but rather requires the broad, interdisciplinary approach represented in our research program and exemplified by the divergent expertise of our researchteam. In the coming years of this research program, we hope to continue our multi-method investigations of linguistic and nonlinguistic functions of prefrontal cortex. The major aims of the research plans outlined in the current proposal are as follows: (1) to continue our investigations of the role of LIFG in language processing; (2) to better characterize the role of LIFG in working memory; (3) to evaluate the relation between working memory, language, and cognitive control and the nature of their dependence on LIFG; and, (4) to develop new tools for inferring causal structure-function relations. This research program has relevance to disorders of mental health (specifically, attentional disorders) and to disorders of language, by virtue of the fact that it highlights the important links between these two seemingly disparate functions.